Metamike shared the photograph on Reddit with the caption: "My dad's best friend came to visit him in the hospital."

According to the Reddit thread, metamike's father was originally admitted to hospital for abdominal surgery. But due to complications, he had to have another round of surgery and ended up staying in hospital for longer than he'd hoped.

Metamike wrote that the surgery had "taken quite a toll" on his dad. But added that when he took his father's dog in to see him, it was "the happiest" he'd been.

He has since received thousands of comments and well-wishes for his dad from across the online community.

One Reddit user wrote: "I know I don't know who you are or why your dad is in hospital, but this picture really touched me and I wish the best to you and your family."